Hybrid and electric cars often employ electrical traction motors which, as with conventional motors, generally include a stator and a rotor. The stator is typically stationary, and the rotor rotates relative to the stator. In alternating current (“AC”) motors, the stator contains a current carrying component generating a magnetic field to interact with the rotor. The rotor in an AC motor may also incorporate a squirrel cage—a cage-like series of conductive bars joined by a conductive structure at both ends.
It is desirable to increase the strength in the squirrel cage of such systems. Prior art systems—which typically incorporate pure aluminum components—do not exhibit optimum strength. Other solutions for increasing strength, such as incorporating steel containment rings that are interference fit on the outer diameter of the cast end rings, are complex and non-optimal, as is the practice of using machined bars and end rings joined after assembly by welding. Both of these methods increase the cost and complexity of manufacturing.
Accordingly, it is desirable to provide methods and systems for increasing the material strength of an induction rotor squirrel cage, compared to conventional pure aluminum, while limiting the reduction in electrical conductivity. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.